1. Field of the Invention
The present invention relates to a scan type exposure apparatus for manufacturing a semiconductor device and a liquid crystal display panel and, more particularly, to a scan type exposure apparatus capable of performing a peripheral exposure without using a dedicated peripheral exposure apparatus.
2. Related Background Art
In recent years, a liquid crystal display panel has been often employed as a display device of a personal computer, a TV set, etc. Further, an areal size of this liquid crystal display panel has increased, to the order of 500 mm.times.500 mm.
This liquid crystal display panel is constructed by effecting patterning of a transparent thin-film electrode in a desired configuration on a rectangular glass substrate by photolithography. An apparatus for this photolithography involves the use of an exposure apparatus for exposing an exposure pattern formed on a mask onto a photoresist layer on the glass substrate through a projection optical system. With the increase in the areal size of the liquid crystal display panel, a scan type projection exposure apparatus has been proposed to enlarge an exposure area of the projection exposure apparatus.
Further, when a resist is coated on the glass substrate by use of a spin coater, it follows that a resist thickness in the vicinity of an edge is larger than in other portions. For this reason, in the case of a positive resist, even when the portion in the vicinity of the edge is exposed with an exposure quantity optimal to the pattern exposure, the resist in close proximity to the edge remains undeveloped, and this may cause generation of particles. Therefore, a dedicated peripheral exposure apparatus has been required.
However, with the increased areal size of the glass substrate, an increase in size of the dedicated peripheral exposure apparatus can not be avoided, resulting in a problem in that a larger space is needed.
Also, when using the peripheral exposure apparatus, there arises a problem in which the number of processes augments, so that throughput decreases.